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Changes in the silver fir forest vegetation 50 years after cessation of active management

100%

Woziwoda B., Kopec D.

Acta Societatis Botanicorum Poloniae

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2015

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tom 84

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nr 2

Knowledge of the vegetation and the monitoring of its changes in preserved areas is an essential part of effective conservation policy and management. The aim of this study was to assess the effectiveness of traditional methods of conservation of silver fir forests. The study analyses the changes in the structure and species composition of a temperate forest excluded from the commercial silvicultural management for 50 years, and since then protected as a nature reserve. The study is based on a comparative analysis of phytosociological reléves made on permanent plots in 1961, 1982, 1994 and 2011. PCA and ecological indicator values were analyzed, as well as characteristic species based on an indicator value (IndVal) index. Results revealed significant and dynamic changes in the forest structure and composition. The mixed coniferous-broadleaved forest with Abies alba and diverse ground flora, considered in the 1960s as valuable and worthy of conservation, was found to have been anthropogenically transformed and unstable. Significant reduction in the human impact was followed by spontaneous regeneration of oak–hornbeam forest. However, the directional process of changes in vegetation was modified by such silvicultural treatments as selective cutting of trees and gap creation, all intended for silver fir maintenance. The results show that Carpinus betulus effectively outcompeted Pinus sylvestris, Picea abies, Quercus robur and A. alba. Changes in the forest overstory and understory caused temporal changes in the habitat conditions reflected in changes in the ground vegetation composition. The proportion of light-demanding and oligotrophic species significantly decreased, while the contribution of species with a wide ecological amplitude, i.e. more shade-tolerant and nutrient-demanding – increased. The share of A. alba was reduced. Species defined in this study as most valuable, should be actively protected, or selection of conservation targets should be re-evaluated.

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Combined effects of earthworms and diurnal temperature fluctuations on successional changes of litter nematode community

80%

Uvarov A. V., Kolosova N., Kulinich O.

Polish Journal of Ecology

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2009

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tom 57

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nr 4

685-696

Earthworm functioning and temperature regime are among the most important biotic and abiotic factors of soil environment; their combined action on soil nematode activities has not been studied. In a 4-month laboratory experiment, effects of the epigeic earthworm Dendrobaena octaedra on a succession of nematode community in litter of a mid-European birch/oak forest were tested in the gradient of an increase of diurnal temperature fluctuations from 0℃ (constant 15℃; T₁₅) to 10℃ (daily range between 10° and 20℃; T₁₀₋₂₀) and 20℃ (daily range between 5° and 25℃; T₅₋₂₅). Earthworm and temperature effects were measured as differences in nematode community respiration rates between the experimental treatments. Nematode respiration rates were calculated on the basis of body size/weight/O₂ consumption relationships for individual species. Nematode community was dominated by bacterial feeders and changed in a characteristic successional pattern which, however, was markedly modified by temperature regime and earthworm activities. Dominant nematode taxa revealed specific patterns of temporal dynamics in connection with their responses to temperature and earthworm presence. Thus, metabolic activity of Plectus acuminatus was strongly reduced by D. octaedra but did not react to variation of temperature regime. In contrast, activity of Panagrolaimus sp. significantly responded to temperature but not to earthworm presence, whereas Pl. thornei reacted to both factors separately and in combination. Ceratoplectus armatus was stronger affected by earthworm presence then by temperature; Tylocephalus auriculatus showed the opposite pattern. The variety of responses may explain the coexistence of several taxonomically related (Plectidae) and trophically similar species within the dominant group. Both earthworm presence and increase of the range of diurnal temperature fluctuations strongly affected the net of interspecific correlations within the nematode community. Earthworms strongly reduced total activities of nematode community at any temperature regime. T₁₅ regime showed markedly lower level of cumulative nematode respiration than both fluctuating regimes, irrespective of earthworm presence. In conclusion, combined effects of earthworms and temperature regime drastically changed patterns of relationships within the nematode litter community. The results of the experiments may have implications for the perspectives of global warming events at the study site: it is suggested that the ultimate vector of the changes in litter environment might be directed towards the conditions of the treatment [T₁₅ regime; earthworms present], with the corresponding trends in the development of the litter nematode community.

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Successional changes and diversity of mesostigmatid mite communities [Acari: Mesostigmata} on reclaimed power plant waste dumps

80%

Madej G., Stodolka A.

Annales Zoologici

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2008

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tom 58

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nr 2

Secondary succession of mesostigmatid soil mites was studied in two types of reclaimed electric power plant waste dumps in Łaziska Górne (Upper Silesia, Poland) in 1997–1998. The dumps on which the studies were carried out differed in their construction and structure. We sampled 6 sites from 2 localities (Sites I–III and IV–VI), representing 3 stages of ecological succession. The sites differed floristically and in substrate physiochemistry i.e. organic carbon content (Corg) and total nitrogen (Nt). Site I representing pioneer stage was characterized by a poorly developed herb layer, a lack of trees and shrubs, and low Corg, Nt and humus content. Sites III, V and VI represented a pre-forest stage and were characterized by a larger number of plant species, higher percent cover of trees and shrubs, and high Corg, Nt and humus content. Sites II and IV represented an intermediate stages of succession. In 18 months, we took 540 samples of soil and litter, and we collected 4811 mites, assigned to 86 species of mesostigmatid mites. The mite communities differed between successional stages, mostly with respect to the relative dominance among species. At the pioneer stage of succession, the mite community was characterized by a “degraded” model of species abundance distribution, with a high dominance of Asca bicornis. At more advanced ecological stages (Sites III, V and VI), mite communities had similarities with communities of forest. Some of the most abundant species in Sites III, V and VI were typical forest inhabitants. Sites I–III represent a real succession of plant communities, soil development and mite communities, showing an increase in species richness of mites, diversity indices and of the number of dominant species (creative type of succession). The succession within Sites IV–VI reveals a different course (rise-and-fall).

Ograniczanie wyników

1 Acta Societatis Botanicorum Poloniae

1 Annales Zoologici

1 Polish Journal of Ecology

1 Kolosova N.

1 Kopec D.

1 Kulinich O.

1 Madej G.

1 Stodolka A.

1 Uvarov A. V.

1 Woziwoda B.

1 2015

1 2009

1 2008

Changes in the silver fir forest vegetation 50 years after cessation of active management

Combined effects of earthworms and diurnal temperature fluctuations on successional changes of litter nematode community

Successional changes and diversity of mesostigmatid mite communities [Acari: Mesostigmata} on reclaimed power plant waste dumps